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DETERMINATION OF THE HUBBLE CONSTANT FROM X-RAY

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DETERMINATION OF THE HUBBLE CONSTANT FROM X-RAY Powered By Docstoc
					DETERMINATION OF THE
                   HUBBLE CONSTANTFROM X-RAY
 AND SUNYAEV-ZELDOVICH EFFECT OBSERVATIONS OF
        HIGH-REDSHIFT GALAXY CLUSTERS




                                                  (Credit: Joy et al. 2001)
                      –
      MAX BONAMENTE UNIVERSITY OF ALABAMA IN HUNTSVILLE
                               –
                  MARSHALL JOY NASA MSFC
                                  –
      SAM LAROQUE, JOHN CARLSTROMUNIVERSITY OF CHICAGO
Sunyaev-Zel'dovich Effect Observations


                    BIMA




                                                            (Credit: Carlstrom et al., (2002)
                   OVRO

                                 Observable: Temperature decrement
                           Clusters of similar mass
                           have a redshift-
                           independent SZE effect




(Carlstrom et al. (2002)
X-ray Observations

    CHANDRA (with BIMA decrement contours overlaid)



                                                                    Observables: Surface brightness




                                  (Credit: Bonamente et al. 2006)
                                                                    and temperature distribution




                            38
 Have SZE/X-ray available for clusters, z=0.14-0.89
 (Bonamente et al. 2006, ApJ 647, 25; LaRoque et al. 2006 ApJ 652, 917)
How to measure distances with X-ray and SZE observations

 Joint use of X-ray and SZE observations




 Without assumptions on cosmological parameters, one can derive simultaneously
distance DA and densityne of the emitting/scattering gas

  Main advantages of this method:
 Independent of Cepheid calibration (no standard candles needed)

                         ~1)
 Reaches high redshift (z
SZE/X-ray sample

          CLUSTER       Z                 CLUSTER       Z
    CL 0016+1609            0.541   ABELL 1689          0.183
    ABELL 68                0.255   RX J1347.5-1145     0.451
    ABELL 267               0.230   MS 1358.4+6245      0.327
    ABELL 370               0.375   ABELL 1835          0.252
    MS 0451.6-0305          0.550   MACS J1423.8+2404   0.545
    MACS J0647.7+7015       0.584   ABELL 1914          0.171
    ABELL 586               0.171   ABELL 1995          0.322
    MACS J0744.8+3927       0.686   ABELL 2111          0.229
    ABELL 611               0.288   ABELL 2163          0.202
    ABELL 665               0.182   ABELL 2204          0.152
    ABELL 697               0.282   ABELL 2218          0.176
    ABELL 773               0.217   RX J1716.4+6708     0.813
    ZW 3146                 0.291   ABELL 2259          0.164
    MACS J1115.2+5320       0.458   ABELL 2261          0.224
    MS 1054.5-0321          0.826   MS 2053.7-0449      0.583
    MS 1137.5+6625          0.784   MACS J2129.4-0741   0.570
    MACS J1149.5+2223       0.544   RX J2129.7+0005     0.235
    ABELL 1413              0.142   MAC J2214.9-1359    0.450
    CL J1226.9+3332         0.890   MACS J2228.5+2036   0.412
    MACS J1311.0-0310       0.490
Models of the gas distribution


 Use three models for the intra-cluster medium:
 (1) Simple isothermal beta model
 (2) Isothermal beta model with 100 kpc cut
 (3) Non-isothermal, hydrostatic equilibrium model with arbitrary temperature
profile and double-beta model density distribution:




                       ,
  Use a MCMC method in which model parameters are used to predict the
 observables:
  surface brightness;
  temperature profile;
  SZE decrement;
 then compare with the observations in order to do parameter estimation.
                                  Examples of non isothermal modeling of intra-cluster medium


                                                          SURFACE                TEMPERATURE PROFILE
                                                          BRIGHTNESS
(Credit: Bonamente et al. 2006)
Hubble diagram (D vs. z) for hydrostatic equilibrium model
                A




                                                   (Credit: Bonamente et al. 2006)
Comparison of Hubble diagrams for all 3 models




                                                                       (Credit: Bonamente et al. 2006)
  “ [The SCDM fits] ... have the same quality as that for the currently favored
                                                                           LCDM
  cosmology, indicating that
                           cluster distances alone can not yet effectively constrain the
  energy density parameters...” (Bonamente et al. 2006)
Other methods to measure the Hubble constant


 Cepheid calibration of secondary distance indicators: Freedman et al. (2001)




                                                                                (Credit: Freedman et al. (2001)
  Cepheid calibration of supernovae type Ia (requires absolute calibration
of peak luminosity): Riess et al. (2004, 2005)




                                                                    (Credit: Riess et al. (2005)
  Indirect measurement from WMAP: Spergel et al (2007)




                                                                       (Credit: Spergel et al. (2007)
“ The CMB data do not directly measure 0Hhowever , by measuringWmH02 [...] the
                                        ;
                                 H
CMB produces a determination of 0 if we assume a simple flatLCDM model” (Spergel et
al. 2007)
 Summary:

After about 80 years, it all seems to hang together for the Hubble constant ...




                                                                            (Credit: Freedman et al. (2001)
                                  Cepheid-based and SZE-based agree on Hubble constant, current uncertainty is 10-
                                  15%
                                                                                                        SZE
                                                                           CEPHEIDS
(Credit: Freedman et al. (2001)




                                                                                                         2006

				
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posted:7/13/2013
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